Chitosan-Fe-Al-Mn metal oxyhydroxides composite as highly efficient fluoride scavenger for aqueous medium.

•Chitosan helps to improve the fluoride adsorption by metal oxides nanoparticles.•Agglomeration of nanoparticles reduces after dispersion into porous polymer.•Interaction among chitosan and metal oxides revealed by XPS analysis.•Polymeric barrier causes unaffected adsorption under ionic strength.•Faster adsorption due to less agglomeration and high porosity in polymer matrix.